v (1)(使)调(交)换位置 ((cause to) exchange or replace (sth) with another)[I，I+prep (with)， I+adv (over/round)， T+n， T+n+prep (with)，T+n+adv (over/round)]：I was on duty last Sunday，but I～ed (with another man). 上周日我值班，但是我(和另一个人)调换了一下。Stop～ing (a)round and keep to one job. 不要经常调换工作，要安心一种工作。～positions/ideas/pocketbooks 交换位置/想法/笔记本;We～ed sides. 我们交换了场地。(husband and wife)～roles (with each other)(丈夫与妻子)交换角色;His parents are always redecorating the rooms and～ing the furniture (a)round. 他的父母总是重新装修房间并且调换家具的位置。〖同〗exchange，change，trade;

(2)(使)改变((cause to) change) [I，I+prep (to)，I+adv (over)，I+adv (over)+prep (to)，T+n，T+n+prep (to)，T+n+adv (over)，T+n+adv (over)+prep (to)]：The lights～ed (from green to red). 灯改变颜色 (由绿色变红色)。He decided to～to a vegetarian diet/another political party/the production of refrigerators. 他决定改吃素食/转而加入另一政党/改产电冰箱。Peter～ed over to teaching/a sensible method/new technique. 彼得转而从事教学/使用一种合理的方法/使用新技术。Having considered that problem，they～ed the conversation (to a more interesting topic). 考虑完那个问题之后，他们换了话题(谈更有趣的话题)。He～ed the lever to the “off” position. 他把控制杆转换到“关”的位置上。The aim is to～the whole country over to natural gas. 目标是使全国改用天然气。

(3)鞭打(whip with or as if with a switch)[T+n]：～one's horse to make it faster 鞭打马使之跑得更快;Grandpa～ed us when we were disobedient. 我们不听话时外祖父就打我们一顿。〖同〗whip;

(4)开，关(电器)((cause an electric current to) begin or stop operation)[I+adv (on/off)，T+n+adv(on/off)]：Please～on/off. 请打开/关掉(机器、煤气、电源等)。～on the television 打开电视;～off the main light/the radio关掉主灯/收音机;～the machine/the electricity off 关掉机器/将电源切断;The equipment/transmitter is～ed on automatically. 这部设备/发射机可自动开机。Make sure the current is～ed off at the mains. 确实保证电流与主干电网断开。

(5)使(火车等)转轨(transfer (trains) from one railroad track to another)[T+n+prep]：～the train to the other track/siding 把火车转向另一轨道/侧线;

(6)很快移(摆)动(move (back and forth) sharply)[I，T+n]：The cat's tail～ed back and forth. 猫的尾巴来回摆动。The horse/cow～ed its tail. 马/牛来回摆动尾巴。～one's hands away 迅速把手移开;〖同〗move，swing;

switch off (v adv) 1)不再听或感兴趣(vi)(fig，infml)：He～ed off when listening to the pop music. 他对听流行音乐不再感兴趣。2)使感到厌倦(vt)(fig，infml)：That lecture～ed most of the students off. 那个讲座使大部分学生感到厌烦。

n(1)开关，电门(device for breaking or opening an electric current，etc)[C]：an electric light～ 电灯开关;a two-way～ 双向开关;press on/off the～按一下接通/断开电源;The～es are down when the power is on and up when it's off. 电源接通时开关向下，电源切断时开关向上。The～must be broken because the wiring is good and the bulb is brand-new. 开关肯定坏了，因为接线没问题，灯泡也是崭新的。〖同〗box，lever，handle，button;

(2)(铁路)道岔，转轨器(device for controlling which line a train follows at points)[C]：The train was derailed when the～failed to work. 转轨器失灵，火车脱了轨。The general's private railroad car is standing on the～. 将军的私人小火车正停在道岔上。

(3)改(转)变(big change in sth，usu one that is not expected)[C](=switch-over)(infml)：a～in the train times 列车时刻的变更;a～of support from one political party to another 从支持一个政党转向支持另一个政党;make a～in one's plans/one's arrangements 改变计划/按排;make a～from an unfriendly manner to a friendly manner/from gas to electricity 由不友好的态度转向友好/由煤气改用电;After several～es of direction they found themselves on the right road. 好几次改变方向之后，他们才发现走对了路。There has been a～in classes between the teachers. 有一次老师们之间相互调课。〖同〗change，alternation，trade，shift;

(4)(树木)软枝条，细软鞭子(slender，flexible rod or stick;rod like this used for whipping)[C]：whip the bad boy with a birch/hickory～. 用桦树/山核桃枝抽打那个不听话的孩子;〖同〗rod，stick;

(5)长假发(thick bunch of real or artificial hair worn as part of hair)[C]：put on a～on the head 头戴假发;

→′switch-blade n 弹簧折刀(=switch knife);′switchboard n 交换台;配电盘;′switchman n 扳道工人;′switch-over n 大转变;′switchyard n铁路调车场